Asbestos is a collective term for naturally occurring fibrous mineral silicate minerals whose inorganic fibres the body can still cough up after a single inhalation, or can no longer break down, depending on the type of fibre. The small fibres of about 5 μm in size and the maximum average size of 3 μm get caught in the lung tissue and are symptomatically noticeable only after many years. Among the different types of asbestos fibres, the white asbestos chrysotile is the most dangerous. It differs in its very fine structure of approx. 0.75 - 1.5 μm and thus carries the greatest risk of becoming trapped in the lungs and not being able to be coughed up.
Special plasma systems from Diener electronic can be used to examine material samples such as lung tissue for inorganic residues such as asbestos.
By drying lung or lymph node tissue from the lung region beforehand, it is possible to remove all organic materials by means of plasma treatment. What remains is inorganic foreign material such as quartz dust, asbestos or physiologically occurring salts or calcium compounds. These residues could be fed to a further analysis and examined. This has real advantages over other ashing methods, especially chemical methods of ashing.
Asbestos used to be popular and well used because of its chemical resistance and ease of further processing. New protection directives have banned the use of asbestos for the most part. In some areas of industry such as electronics, it is still used, but only in a few countries. A distinction is made between strongly bonded and weakly bonded asbestos, and depending on the bond, it is of course more or less harmful to humans. If the bond is strong, as in cement, for example, the asbestos content is very low and very strongly bonded. Whereas sprayed asbestos, for example, has a much higher asbestos content and is also much more weakly bonded. This means that the asbestos can dissolve out over time, whether through weathering or external effects such as vibrations, and get into the environment. At this point it becomes harmful to humans.
To protect against this, a room air analysis for asbestos is recommended, following the guidelines of VDI 3492. Similar to the process of ashing lung tissue samples, house dust samples can also be ashed and analysed for asbestos. Or let the room air pass through a filter for several hours, which catches the asbestos fibres and makes them visible later under a scanning electron microscope.